Since its founding in 2002, Nanosolar has raised a lot of money – half a billion dollars to date – and made a lot of noise about upending the solar industry, but the Silicon Valley start-up has been a bit vague on specifics about why it’s the next big green thing.

On Wednesday, Nanosolar pulled back the curtain on its thin-film photovoltaic cell technology — which it claims is more efficient and less expensive than that of industry leader First Solar — and announced that it has secured $4.1 billion in orders for its solar panels.

The typical Nanosolar farm will be between 2 and 20 megawatts in size, Mr. Roscheisen said in an e-mail message from Germany, where he was attending the opening of Nanosolar’s new factory near Berlin. “This is a sweet spot in terms of ease of permitting and distributed deployment without having to tax the transmission infrastructure.”

First Solar, the Walton family-backed (WMT) maker of thin-film photovoltaic modules, on Thursday announced its second solar power plant. The latest project is a 10-megawatt photovoltaic power station to be built for Sempra Generation (SRE) in Nevada. Two weeks ago, California regulators approved a 7.5-megawatt – expandable to 21 megawatts – First Solar (FSLR) power plant to be constructed in the Mojave to generate electricity for utility Southern California Edison (EIX). Thin-film solar technology layers solar cells on plates of glass or flexible materials, a process that lowers production costs with the trade-off being lower efficiency at converting sunlight into electricity.

What’s notable about the Nevada First Solar project is that it will be constructed adjacent to a Sempra natural gas-fired power plant near Boulder City, Nev. That will allow the solar station to share transmission lines and other infrastructure and minimize land use. Those are no small considerations these days as the solar land rush continues in the Mojave and environmentalists grow uneasy over the impact of industrializing the desert.

Tempe, Ariz.-based First Solar has already broken ground on the project with completion expected by the end of the year. That’s record time, given that solar thermal power plants – which tend to be larger by orders of magnitude – can take years to receive regulatory approval and build. Also of note: The solar modules for the project will be manufactured at First Solar’s Ohio factory, one of only two commercially operating thin-film manufacturing facilities in the United States. (The other is Energy Conversion Devices’ thin-film factory in Michigan.)

Sempra Generation, a division of utility giant Sempra, will own and operate the First Solar plant, which will supply electricity to Nevada and California.

About Green Wombat

Green Wombat is written by
Todd Woody, a veteran environmental journalist based in California who writes for The New York Times, the Los Angeles Times, Grist and Yale e360. He's one of the few people on the planet who have held a northern hairy-nosed wombat in the wild.

Todd formerly was a senior editor at Fortune magazine, an assistant managing editor at Business 2.0 magazine and the business editor of the San Jose Mercury News.